1936 Indian Head Nickle problem

what is broadstruck?

Ruben

 

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A broadstruck coin is a coin that is struck without the collar in place. When a coin is struck the pressure from the die akes the metal expand outward radially from the center of the coin. Normally there is a collar aound the planchet to restrain this expansion, create the reeded edge if any, and to force the metal upwards and form the rim. If the collar is not present because it gets jammed down around the lower die the coin expands outward to a larger than normal size. How much larger depends on the force of the strike, the metal the planchet is made of, and how well annealed the planchet is.

 

Thanks Conder101...one thing though. I thought the rim was made before the imprint is hammered by the dies onto the Panchette

 

No, that come from improper use of terms when they describe how planchets are made, and how people describe how to tell a blank from a planchet. A blank is the flat disk punched from the strip of metal. The blanks are then put through an upsetting mill and receive and upset edge. (A thickened area around the edge where the blank has been compressed inward by the upsettng mill.) This is where the problem come in. Many people call this an upset rim, or they say what distinguishes the blank for a planchet is that the planchet has a rim on it. But look at a planchet and you will see that the "rim" on it looks nothing like the rim on the finished coin. That upset edge does help to FORM the rim on the coin, but it still needs he restrainng of the collar to form it properly and more completely.

 

Oh I didn't doubt it needed a restraining collar. I was just repeating what I heard in the US Mints videos

How did you aquire this expertise? Have you worked for the mint?


Ruben

 

Maybe, but understanding how coins are produced might take some visual aid.

Ruben

 

Here's how Britian makes Silver coins http://www.youtube.com/watch?v=DkHFNnOK3Bg&NR=1

Here's how Germany makes gold coins for Bhutan http://www.youtube.com/watch?v=Ef_wJH4z5Dw&feature=related

and the Royal Canadian Mint http://www.youtube.com/watch?v=4wwWxSNgI08&NR=1

 

Thank YOU!

 

I digress, but...

Earlier in the thread when discussing weights...

An easy way to test the weight of an unknown coin is to test it against the weight of a known coin.

Take a pencil and a Popsicle stick. Lay the pencil on a table. Balance the stick on the pencil. (Maybe add a drop of glue... don't have to... but it helps to stick the stick to the pencil.) Place the known coin (in this case the legit 36) on one end of the stick. Place the other coin on the other end. If the coins are the same weight the stick balances on the pencil. If it doesn't balance, which ever is heavier will sink. How quickly it sinks give you an idea of how much heavier (or lighter) the unknown coin is.

 

A quick off-topic physics lesson -

Acceleration imparted by gravity is independent of the mass (weight) of an object. A light object will fall at the same rate as a heavy object. You can not judge the mass of an object by how fast it falls or tips a balance.

At any rate, the end of a popsicle stick balanced on a pencil is about 2 inches from the balance point and maybe .25 inches from the base it's resting on. I doubt that anyone could even come close to visually judging the time it takes for a full deflection.

This is all discounting the effects of friction at the fulcrum. If you put a one-grain weight on a balance scale, the scale will react far slower than if you put a brick on the same scale. However, when balancing two nearly equal weights the affects of friction are negligible.

 

yada yada yada.... Physics Schmisics

Practical Application
works all day long separating the 82 Zincolns from the 82 Coppers.

 

squeezing force probably thru leather or rubber

Post mint. Notice that all the devices & the coin diameter are all spread evenly. It is not a broadstrike and I doubt this damage was done to a wrong planchet error. The normal coin may have been squeezed or hammered to the larger diameter. The squeezing force was probably done through leather or rubber so that the force was imparted evenly to the surface.
Very best regards,
collect89

 

42 years as a numismatist reading everything I can get my hands on, including books on error coins. Looking at coins and trying to figure out what would have to happen in order to get the effect I'm seeing. Thinking about exactly what happens during the striking of a coin slowing down the process mentally and seeing what is going on, how the metal is moving, where it is moving to. One thing I think every collector really needs, and few have is a THROUGH understanding of how coins are made.

There are still some things that I don't understand. I need a better understanding of the blanking process. A clipping blank is formed when the strip fails to feed properly or the punch press fails to shift properly. (The punch press has either one row of punches tha shifts from side to side about one radius between punches, or two row with the second row offset one radus. This allows more planchets to be punched from the strip.) Now with this setup I can easily see how ou can get a straight clip, a curved clip, two straight clips, a straight and a curved or two curved clips. I could also see a Y or a bowtie fragment. Now the two straight or straight and curved clip combinaion should be 90 degrees apart, and the two curved clips should never be 60 degrees apart or 180 degrees apart. But yet they do come at different separations. And I can't see how you could have me than two clips yet multiple clips are known.